This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We have developed a novel probe that, when used in conjunction with SSFDPM, can be used to determine the optical properties of in-vivo superficial tissue. This project seeks to quantitatively characterize the probe performance and identify key parameters that impact the interrogation depth.